What’s the best way to evaluate medical information?

There are four basic questions you should ask yourself to evaluate the promised benefits of a medical treatment or procedure, according to researchers at the Center for the Evaluative Clinical Sciences at Dartmouth Medical School: What is the assertion? If true, would you care? Who stands to benefit from the assertion? How good is the evidence, that is, does it come from multiple studies (or just one) and how good are those studies?